A conventional induction hob comprises a (e.g., glass-ceramic) solid plate, as well as a number of (e.g., copper) coils placed underneath it and selectively operable for defining one ore more cooking zones.
During operation, after a (e.g., ferromagnetic—such as stainless steel or iron) cooking pan containing food to be cooked is rested on a cooking zone, an alternating electric current is allowed to flow through the respective coil(s), thus generating an oscillating magnetic field. According to well known physical principles, such magnetic field induces an eddy current in the pan, which in turns produces (by Joule effect) resistive heating thereof and hence of the food contained therein.
The induction effect causes heating only of the plate area (of the activated cooking zone) actually covered by the (bottom of the) pan, and only upon contact with it. Therefore, during cooking operations, the induction hob prevents burn injury when touching any plate area free from pans or in close proximity thereto. Moreover, thanks to poor heat-conducting properties of the glass-ceramic material, burn injury is also significantly reduced for those plate areas (of activated cooking zone(s)) which pan has just been removed from.
This allows implementing advanced and safe induction hobs with touch-sensitive control panel directly on the plate.